Mechanically, p-PI3K, p-AKT (Thr473), p-GSK3β and Sox2 levels were reduced after treating with Caffeine in GC cell lines, suggesting Caffeine might mediate the expression of Sox2 and the activity of PI3K/AKT signaling pathway (Additional file 1: Fig. S9C). This evidence concerns the gene GSK3B and gastric cancer.